The invention concerns an applicator brush for liquid or pasty media, in particular for decorative cosmetics such as mascara, with a rod-shaped support the outer side of which has a plurality of injected fingers of plastic material which are disposed at mutual separations to project radially in different directions. The invention also concerns a method for producing a corresponding applicator brush.
Applicator brushes of this type can be used for different purposes. The application of so-called mascara is described below. The inventive applicator brush can also be used for coloring strands of hair, and for applying pharmaceuticals or cleaning agents.
An applicator brush for mascara should simultaneously satisfy different requirements to permit advantageous application of the mascara. The applicator brush should at least comb the eyelashes and optionally the eyebrows before applying the mascara, thereby aligning them in the desired fashion. The applicator brush should accept a sufficient amount of mascara to permit coloring of all eyelashes or hair therewith, while avoiding frequent dipping of same into the mascara supply container. Since the mascara should be applied uniformly and without spilling, there can be no excess mascara on the applicator brush. Towards this end, the applicator brush is usually wiped off when pulled out of the supply container.
Since the applicator brush is formed as a freely projecting component having a handle at one end, it must be sufficiently stable to absorb the forces exerted during use to prevent it from breaking. On the other hand, the applicator brush must be flexible enough to adjust to the curvatures of the eyelids and eyebrows and must yield sufficiently during improper use to prevent injuries to the eye region.
To prevent user allergic reactions, the applicator brush should contain no metal and mold fungus and bacteria contamination should be largely prevented. This can be achieved e.g. in that unused residual mascara does not cling to the applicator brush, since these residual amounts are a good basis for mold fungus and bacteria growth.
The applicator brush can be used for applying mascara onto the eyelashes and also for applying mascara onto the eyelids as so-called eyeliner.
When the supply container is empty, the applicator brush is usually disposed of therewith. Since the applicator brush is relatively expensive to manufacture compared to the mascara, it should be produced as inexpensively as possible.
The known applicator brushes satisfy only some of the abovementioned requirements and have further disadvantages.
It is known to dispose a plurality of short bristles between several wires and twist them such that the bristles are held between the wires. Such a twisted applicator brush, which is mostly used today as a mascara applicator, is described e.g. in U.S. Pat. No. 4,982,838. A substantial disadvantage of a twisted applicator brush is that a large portion of the mascara is retained in the regions formed between the bristles during use, due to the compact arrangement of the bristles, in which dirt, e.g. spores or bacteria can develop. Moreover, such an applicator brush does not provide uniform combing of the eyelashes or hair due to the plurality of densely packed bristles, since the bristles cannot engage with the eyelashes or hair in a combing fashion.
To improve the combing action, DE 80 26 372 U1 has attempted to incorporate an asymmetric bristle support into the twisted wires. A construction of this type is very demanding and does not actually improve the combing effect since the plurality of bristles form a surface which blocks the eyelashes or hair such that the hair cannot penetrate between the bristles to an extent which would be required to obtain a good combing effect.
The production of twisted applicator brushes is also relatively expensive since the wires and bristles are produced individually and the bristles must be subsequently twisted into the wires, which is complicated from an apparatus point of view. The bristle ends must also be thereby deburred and ground to prevent the ends from having sharp edges which could cause injuries. A further additional disadvantage of twisted applicator brushes is that the metal core formed from the twisted metal wires can bend during use which makes the applicator brush useless and presents a great danger to the eye region of the user.
To eliminate the disadvantages of twisted applicator brushes comprising a bristle stock, an applicator brush was developed which comprises injected fingers (described in DE 80 10 740 U1) on which the pre-characterizing part of claim 1 is based. An applicator brush of this type has a relatively rigid tubular support with injected plastic coating having radially outwardly projecting fingers formed in one piece therewith, the fingers having a constant cross-section throughout their length. Attempts were made to improve the combing effect of this applicator brush by giving the individual fingers sufficiently large mutual separations. However, this caused the amount of mascara accepted in the spaces between the fingers to be insufficient. If the fingers are disposed at smaller mutual separations, a sufficient amount of mascara can be received, however, the combing effect is inadequate, since the eyelashes and hair cannot or can only insufficiently penetrate between the fingers. DE 80 10 740 U1 tries to increase the reception capacity for mascara by profiling the fingers. This slightly reduces the above-mentioned problems but does not eliminate them completely.
The desired sequence of combing effect and subsequent application of mascara and optionally renewed final combing is not guaranteed by the applicator brush of DE 80 10 740 U1. Moreover, it does not bend under the application of small forces due to the relatively stiff, central support such that optimum adjustment to the curvature of the eyelids or eyelashes is not ensured.
It is the underlying purpose of the invention to produce an applicator brush of the above-mentioned type which reliably achieves a good combing effect and good, uniform application of the medium to be applied.
This object is achieved by an applicator brush of the above-mentioned construction in that the fingers have a cross-section which tapers towards their free end and are made, together with the carrier, from an elastic plastic material, in particular an elastomeric plastic material.
The outwardly tapering shape of the fingers ensures that the foot sections of the fingers, where they are connected to the support, have smaller mutual separations than the free ends thereof. The larger separation at the free ends of the fingers ensures that they can easily engage the hair and eyelashes in a combing fashion. Due to the relatively large mutual separation, none or only a small amount of mascara is received in the region of the finger tips which can be almost completely removed by a conventionally provided wiper such that the tip region of the fingers substantially contains no mascara and exercises a pure combing effect. Consequently, the eyelashes and hair are combed before contacting the mascara which is accommodated in the foot region of the fingers. It has turned out that in this fashion, the eyelashes can be excellently pre-positioned before applying the actual mascara.
Due to the relatively small separation between neighboring fingers in their foot region, a sufficiently large amount of mascara can be received to generally avoid frequent dipping of the applicator brush into the supply container.
The inventive applicator brush is also advantageous in that the eyelashes and hair are combed again after application of mascara by moving the finger tips of the applicator brush through the eyelashes with decreasing pressure.
The support and the fingers are formed in one piece from a soft-elastic plastic material to ensure that the applicator brush adjusts to the curvatures of the eyelids even at low pressures thereby reliably preventing breaking of the applicator brush. The applicator brush deforms under excessive pressure but returns into its original shape after pressure-relief.
As mentioned above, the carrier and the fingers are formed in one piece from plastic material. To adjust the stability of the support to the desired purpose of application, the support can be provided with local reinforcing inserts. The shape, arrangement and size of the reinforcing inserts permits exact and simple adjustment of the flexibility of the applicator brush to the desired application.
Advantageously, the reinforcing insert is rod-shaped and extends in the longitudinal direction of the support. It can project from the support such that the projecting part of the reinforcing insert forms a retaining or mounting section at which the applicator brush can be grasped directly or mounted to another holding part.
In a preferred embodiment of the invention, the reinforcing insert consists of plastic material, in particular fiber-reinforced plastic material, e.g. fiber-glass reinforced polypropylene, and the support including fingers is injected onto the reinforcing insert. The reinforcing insert preferably extends over more than half the length of the support and, in particular, over approximately 80% of its length, wherein the material of the support covers the reinforcing insert with sufficient strength to provide the applicator brush in total with sufficient elasticity and flexibility. Preferably, the diameter of the support is three to five times larger than the diameter of the reinforcing insert such that the coating of the reinforcing insert with the elastic plastic material of the support has a thickness of one or two times the diameter of the reinforcing insert.
In a preferred embodiment of the invention, the fingers taper substantially throughout their entire length, from their foot region to the tip region. It is also possible to provide sections of the fingers, e.g. the foot region, with a constant cross-section.
The fingers can have a plurality of different cross-sectional shapes, such as a circular or polygonal cross-section, i.e. a conical or pyramid shape. The fingers may also have a crossed, C- or Y-shaped or annular cross-section. The cross-sectional shape can be selected to provide as large as possible acceptance or continuous delivery of the medium to be applied. The entire applicator brush can comprise fingers of uniform cross-sectional shape. Alternatively, the support comprises fingers having different cross-sectional shapes.
In contrast to the above mentioned twisted bristles, the injected fingers can assume exactly defined positions with respect to one another. This permits precise adjustment of the amount of mascara received and delivered and permits removal of most excess mascara using wipers. In a preferred development of the invention, the fingers are mutually oriented in several planes, separated from one another in the axial direction of the support, wherein selection of the separation between the planes permits adjustment of the application properties of the applicator brush to the medium to be applied. The fingers disposed in one plane are preferably evenly distributed across the circumference of the support, with three to six fingers being disposed in one plane. The fingers in the subsequent planes can be arranged in the same fashion or can be displaced in the circumferential direction of the support.
A first embodiment provides that the fingers are aligned in rows extending in the longitudinal direction of the support, in particular, if there are several evenly spaced planes of fingers. Alternatively, the fingers can be disposed in at least one row extending helically about the support. Sections without fingers may also be provided in the longitudinal direction of the support and in the peripheral direction.
The diameter of human eyelashes is approximately 0.05 to 0.08 mm and of the eyebrow hairs, approximately 0.03 mm to 0.10 mm. In a preferred embodiment of the invention, the separation between neighboring fingers in their foot region is between 0.03 mm and 0.1 mm and, in particular, approximately 0.05 mm. This ensures that a single hair can be accommodated between the foot regions of the fingers and minimizes the chance that several hairs thread between two fingers. Optionally, a separate region can be provided for treating the eyelashes and eyebrows, wherein the separation between the fingers is optimally adapted to the respective hair in that the fingers are disposed on the support in at least two regions having different mutual separations.
In a preferred embodiment of the invention, the fingers can have differing radial lengths. This ensures that the longer fingers comb and align the eyelashes and hair before mascara is applied by the shorter fingers. This is the case in particular, if short and long fingers are alternately disposed in the axial direction of the support.
The application properties of the applicator brush can also be influenced when the surface of the fingers is not smooth but structured. The surface can be e.g. wavy, curled or toothed. In particular, the fingers can have surface depressions for receiving the medium to be applied. The depressions are formed e.g. as small blind holes for storing mascara from which it is gradually and uniformly delivered.
In a further development of the invention, the free ends of the fingers are split several times such that the finger tips are preferably formed like a brush. This ensures that the applicator brush can also reach and comb very fine hair.
The fingers and the support can be made from the same plastic material. Alternatively, fingers of different plastic materials can be disposed on the support thereby providing different combing and application effects, which are recognizable to the user.
The front free end of the support is usually rounded to prevent any risk of injuries. In accordance with the invention, this region can be used for application if the front free end of the support comprises several axially extending fingers. This permits drawing of relatively thin mascara lines using the applicator brush, which permits additional use of the applicator brush as an eyeliner.
The mascara is usually received in the foot region of the fingers by dipping the applicator brush into a mascara supply container. Alternatively, the mascara can also be guided to and exit from the fingers via internal channels. This can be effected e.g. in that the support has one or more internal axial channels into which the medium to be applied can be supplied, wherein the fingers and/or intermediate sections are provided with outlet channels which connect the axial channels to the outside of the applicator brush. The outlet channels either open into the foot region between two neighboring fingers or can extend through the fingers to the finger tip region. A user can support transport of the mascara in the axial channels and in the outlet channels by compressing a section of the axial channel in a region of the support provided therefor to achieve a pumping effect.
In a further embodiment of the invention, the support has an inner axial channel in which a holding means, in particular a holding bar, of at least one additional applicator is guided in an axially displaceable fashion such that the additional applicator can be extended at the front end of the applicator brush and be retracted into the axial channel. The additional applicator can thereby be used as an eyeliner or can be adapted in any other manner to a further application function.
In a further development of the invention, two coaxial holding means are provided in the inner axial channel each of whose front ends carries one additional applicator. The coaxial holding means can be displaced relative to one another and relative to the support to permit optionally extending one or both additional applicators or retraction thereof into the support.
When the applicator brush is not used it must be accommodated in a casing which substantially tightly surrounds it. Conventional applicator brushes are inserted into a casing. A further development of the invention provides that the support comprises a guiding part at its rear end which is slidably received in a casing. Displacement of the guiding part within the casing permits adjustment of the support and fingers between a usage position projecting from the casing and a resting position withdrawn into the casing. Such an extendable applicator brush is advantageous in that the user does not need to separate the applicator brush from the supply container and keep same in her/his hand during use of the applicator brush. Moreover, the inventive design permits use of the applicator brush with one hand, wherein the applicator brush can thereby be easily brought into its position of use.
The casing and the inserted applicator brush are preferably separated from the surroundings via a wiper diaphragm disposed on the casing through which the support penetrates when removing the applicator brush, the wiper diaphragm having a passage shaped in correspondence with the arrangement of the fingers on the support. When extending the support or the fingers, the diaphragm wipes off excess mascara and retains it in the casing. The diaphragm is preferably merely cut or tightly slit to guarantee sufficient sealing of the casing interior in the undeformed state while allowing extension and withdrawal of the support and fingers.
The inventive applicator can be produced in one single step using single or multiple component injection method to facilitate inexpensive production. The reinforcing insert, which consists of a first plastic material, is thereby injected with a second elastic plastic material for forming the support and the fingers which are connected in one piece therewith. The reinforcing insert can either be prefabricated and subsequently be introduced into the injection mold or can be produced or injected directly in the injection mold in a previous step.
Further details and features of the invention can be extracted from the following description of embodiments with reference to the enclosed drawing.